[R-meta] [netmeta] Error message in network meta-analysis: "Problem with multi-arm studies: Studies with inconsistent treatment estimates"

Sat Feb 22 17:24:36 CET 2020

Dear Rebecca

If the values you have transcribed are what it published then that 
suggests, not for the first time, that a typo crept into the published 
version. If you cannot contact the authors to clarify I would suggest 
the error here is small and it is unlikely to makea substantive 
difference if you increase the tolerance so that trial passes the check.

Michael

On 21/02/2020 18:54, Rogasch, Rebecca Manuela Madeleine wrote:
> Dear experts,
> 
> 
> first of all, I want to thank you again for your help!
> 
> I am very thankful and really appreciate that you took time to answer my Questions.
> 
> Dear Gerta R�cker, I apologize for the late Response, your Reply in the Mailing list hadn't reached me for some reason
> 
> but was forwarded to me now.
> 
> 
> The Problem is Pretty much solved after entering the data in the Format you suggested.
> 
> 
> I no longer get an error for any of the nine 3-arm-studies, except for one - study "34".
> 
> 
> Output when applying "details.chkmultiarm":
> 
> 
> Multi-arm studies with inconsistent treatment effects:
> studlab treat1 treat2        TE        resid
>         34     PE    SIT -0.144613  0.00143599
>         34     PE     WL -1.855309 -0.00143599
>         34    SIT     WL -1.706388  0.00143599
> Legend:
> resid - residual deviation (observed minus expected)
> TE - treatment estimate
> 
> I checked the data that I entered many, many times and compared it to the values in the paper.
> 
> The values are correct, the data structure should be correct now.
> 
> 
> I am puzzled  - and feeling a bit uncomfortable asking this last Question.
> 
> But I am hoping that someone has an Explanation?
> 
> 
> Best regards,
> 
> Rebecca
> 
> 
> ________________________________
> Von: Rogasch, Rebecca Manuela Madeleine
> Gesendet: Samstag, 8. Februar 2020 14:38:23
> An: Guido Schwarzer; r-sig-meta-analysis using r-project.org
> Betreff: AW: [R-meta] [netmeta] Error message in network meta-analysis: "Problem with multi-arm studies: Studies with inconsistent treatment estimates"
> 
> 
> Thank you very much for the quick Reply and your advice!
> 
> 
> That Explanation makes a lot of sense.
> 
> I have now tried using pairwise() to calculate the SMDs:
> 
> 
> paired<- pairwise(list(TR1, TR2),
>                 n = list(n_TR1, n_TR2),
>                 mean = list(Mt2TR1, Mt2TR2),
>                 sd = list(SDt2TR1, SDt2TR2),
>                 data = DATA1, studlab = studlab, sm= "SMD")
> 
> 
> 
> This is an exerpt from the data Frame;
> 
> 3-arm study in Purple:
> 
> 
>     studlab treat1 treat2 n1 mean1   sd1 n2 mean2   sd2           TE      seTE   age females    severity      income
> 1        1   EMDR     WL 15 22.87 20.27 14 54.21 16.26  -1.65116388 0.4387386 36.54    0.76    clinical      lowmid
> 44     100    NET     WL 19 55.07 27.01 19 76.86 17.14  -0.94310177 0.3439769 29.40    0.31    clinical high income
> 45     104    NET   PsEd 17 19.10 11.70 12 21.20  9.40  -0.18860625 0.3779770 32.85    0.62    clinical      lowmid
> 48     107    MBI   PsEd 68 46.90 18.20 66 55.20 15.30  -0.49022797 0.1754460 47.04    0.17    clinical high income
> 47     107     PE   PsEd 68 50.60 18.50 66 55.20 15.30  -0.26905282 0.1735963 47.04    0.17    clinical high income
> 46     107     PE    MBI 68 50.60 18.50 68 46.90 18.20   0.20049752 0.1719418 47.04    0.17    clinical high income
> 78      11    MBI     WL NA    NA    NA NA    NA    NA  -0.48920000 0.2800000 51.80    0.99        <NA> high income
> 
>       sample arms        self_exp n_total        tr_size   analysis
> 
> 1  refugees    2      self-rated      29     very small completers
> 44 refugees    2 clinician-rated      38     very small        ITT
> 45 refugees    2      self-rated      29     very small        ITT
> 48   vetmil    3      self-rated     134          large        ITT
> 47   vetmil    3      self-rated     134          large        ITT
> 46   vetmil    3      self-rated     136          large        ITT
> 78 civilian    2      self-rated      71 small-moderate        ITT
> 
> 
> 
> However, I still get the same error message in the Network meta-Analysis.
> 
> A more detailed copy of the Output is available if needed.
> 
> 
> Any advice is very much appreciated!
> 
> Best regards,
> 
> Rebecca
> 
> ________________________________
> Von: Guido Schwarzer <sc using imbi.uni-freiburg.de>
> Gesendet: Freitag, 7. Februar 2020 17:49:50
> An: Rogasch, Rebecca Manuela Madeleine; r-sig-meta-analysis using r-project.org
> Betreff: Re: [R-meta] [netmeta] Error message in network meta-analysis: "Problem with multi-arm studies: Studies with inconsistent treatment estimates"
> 
> Hi Rebecca,
> 
> I assume the problem is related to calculating SMDs in multi-arm
> studies. Each pairwise comparison (in a multi-arm study) uses a
> different pooled standard deviation to calculate the SMD which leads to
> inconsistent effects.
> 
> You could / should use pairwise() to calculate the SMDs which considers
> the same pooled standard deviation to calculate the SMD in multi-arm
> studies.
> 
> Best wishes, Guido
> 
> --
> Dr. Guido Schwarzer
> Institute of Medical Biometry and Statistics,
> Faculty of Medicine and Medical Center - University of Freiburg
> 
> Postal address: Stefan-Meier-Str. 26, D-79104 Freiburg
> 
> Phone: +49/761/203-6668
> Mail: sc using imbi.uni-freiburg.de
> Homepage: http://www.imbi.uni-freiburg.de
> 
> ORCID iD: https://orcid.org/0000-0001-6214-9087
> R-book: https://www.springer.com/gp/book/9783319214153
> 
> 
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> 
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> 
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-- 
Michael
http://www.dewey.myzen.co.uk/home.html